Pool Bonding – Dos and Don’ts

I recently read an article in “Pool and Spa News” by Rebecca Robledo that highlighted the dos and don’ts of pool bonding.  I have worked as a pool builder for about ten years and thought that what I had be taught about bonding was 100% correct.  One thing that I did learn about bonding that still seems to be true is that to do it right depends on which inspector you get on the job.  We would get different information from each inspector that came out to do the bonding inspection.  One would say “yeah everything looks good” so on the next pool we would do it that same way.  Then a different inspector would come out for that job and say ” well you need to have a lug at each corner of the pool” or something like that.  So it got to the point where we would know the basics and have to be open to whatever the inspectors said.  For some of us this started to become more of an irritation than it should have been.  We all thought that there should be a specific set of rules to be followed when it comes to bonding, and in fact there is.  The problem, I think comes from the confusing wording in which the codes are written which leaves them somewhat open to interpretation.  So by the time the inspector comes out he has his own interpretation of what is written in the code and that may be a bit different from the interpretation of another inspector regarding the same code.  So today I want to use the information I have learned in the article in an effort to help clear up some things.

First of all there is a difference between “grounding” and “bonding.”  It seems as though some don’t know the difference and use the terms interchangeably.  For the record “grounding is meant to protect people against a possible fault in the electrical system by electrically attaching a piece of equipment to the earth.  “Bonding” electrically ties all metallic elements together to minimize the differences in voltage.  Everything from the light, ladders, and hand rails to the steel walls, coping and rebar get bonded.  There are some other elements that would need bonded as well and I will get to those here momentarily.  One of the common bonding mistakes outlined in the article is the failure to bond thoroughly.  This issue stems from not knowing exactly what needs bonded.  To shed a little light on this just know that any metal within 5 feet of the water needs to get bonded.  Including the ladder and all ladder/handrail sockets, hand rails, light niches, dive stands, coping, and the metal walls of the pool.  If it’s metal and within 5 feet of the water then it needs to be bonded.

The rebar must also be bonded as well as any steel supports around the pool.  They must also be bonded within 3 feet of the interior pool wall.  Another thing regarding the rebar is that simply wrapping the bond wire around it is not sufficient.  Doing that will not create a proper connection.  You will need to use the correct connection clamps or lugs to ensure that any current present has a clear path to follow.  When it comes to what type of wire to use for bonding it is recommended to use a solid copper wire rather than a stranded wire.  The reason is that the strands are more susceptible to damage by the environment since the bond wire will be in direct contact with the earth.  Some inspectors might tell you that certain plastic or fiberglass elements of the pool also need to be bonded.  This is not necessarily true.  Being that fiberglass and plastic are not conductive there would be no reason/need to bond them.  The issue may arise though if for instance the filter has a metal tension band around it.

The inspector may see that and think that because it is metal and if it is within 5 feet of the water that it needs to be bonded.  However if the filter is plastic or fiberglass and sits on a plastic or fiberglass stand then the metal band around it is not in contact with any electrical connection and therefore is not required to be bonded.  Unfortunately that may not appease the inspector and you may find yourself relocating the filter further from the water.

For more information regarding proper bonding and grounding of your swimming pool check out the article in the December 13 2003 issue of Pool and Spa News.  Also, always respect the inspector, ultimately it is his say so that allows you to build the pool.  Codes vary from place to place so be sure to check with your local building department to verify the specifics when it comes to electrical bonding.